Emergence of Concurrent Multiple EGFR Mutations and MET Amplification in a Patient With EGFR-Amplified Advanced Gastric Cancer Treated With Cetuximab.

Chromosomal instability is one of the characteristics of gastric cancer (GC)[1],[2] associated with frequent amplifications of receptor tyrosine kinase (RTK)-related genes. We present a patient with I EGFR i -amplified GC who acquired substantial numbers of I EGFR i mutations and I MET i amplification during the cetuximab treatment as detected by serial ctDNA sequencing. The number of I EGFR i mutations (range, 1-7; Fig 3C) or known actionable I EGFR i mutations (range, 1-6; Fig 3D) were lower than those seen in our GC patient with 22 I EGFR i mutations, including seven known actionable mutations. [Extracted from the article]